D4701A Datasheet | NEC

DATA SHEET MOS INTEGRATED CIRCUIT µPD4701A INCREMENTAL ENCODER COUNTER DESCRIPTION The µPD4701A is a counter for an X, Y 2-axis incremental encoder. When a two-phase encoder signal is input for the X and Y axes, direction discrimination and putation is performed, and count data is output in 8-bit parallel form. In addition, a 3-contact-point input buffer is incorporated, which is useful for applications which use a pointing device such as a mouse or track-ball. The CPU checks the switch input flag or count flag and reads the 12-bit count data in two operations, one for the lower byte and one for the upper byte. The key input flag is output together with the count data in the upper byte. Features - X, Y 2-axis incremental encoder counter - Counter input (Schmitt-triggered input) X axis: XA, XB 2-phase signal   4-multiplication count method used Y axis: YA, YB 2-phase signal  - Counters: 12-bit binary up/down counters (2 sets, X & Y) Reset value: 000H - Count data output: 8-bit parallel latch output × 2 (including key input flag) - On-chip 3-contact-point key input buffer circuit - CMOS - Single +5 V power supply PIN CONFIGURATION (Top View) PIN NAMES XA, YA : A-phase inputs XB, YB : B-phase inputs XA XB RESET X YA YB RESET Y RIGHT LEFT 1 2 3 4 5 6 7 8 9 10 11 12 24 23 22 21 20 19 18 17 16 15 14 13 VDD D7 D6 D5 D4 D3 D2 D1 D0 CS X/Y U/L  LEFT  Key inputs MIDDLE  RIGHT CS X/Y U/L D0 to 7 CF SF : Chip Select : X/Y Counter Select : Upper/Lower Byte Select : Data outputs : Count flag : Count flag RESET X  Counter  RESET Y  reset inputs MIDDLE SF CF VSS ..net (O. D. No. IC-6947A) Document No. IC-3303 (1st edition) Date Published March 1997 P Printed in Japan © µPD4701A ORDERING INFORMATION Part Number Package 24-pin plastic DIP (600 mil) 24-pin plastic SOP (375 mil) µPD4701AC µPD4701AGT BLOCK DIAGRAM XA XB Phase Determination and Edge...